Continuous high speed method for making a commingled carpet yarn

ABSTRACT

A continuous, high speed (greater than 800 meters per minute) process and apparatus enable the production of a multifilament carpet yarn having a degree of filament intermixture high enough so that a standard deviation of less than 6.0 results upon conducting a Standard Yarn Streak Potential Test, as described herein. The apparatus and process allow the production of a multicolored carpet yarn which exhibits a reduced tendency to streak and an increased retention of tip definition.

This is a divisional of co-pending application Ser. No. 07/243,170,filed on Sept. 8, 1988, which is a continuation of application Ser. No.06/895,648, filed Aug. 12, 1986, now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to the fields of textile manufacturing,processes for shaping or treating plastic articles, textile spinning,twisting, and twining and textiles, fluid treating apparatus.

With respect to the field of textile manufacturing, the presentinvention is related to the areas of (a) thread finishing by diversefinishing operations; (b) thread finishing by texturing (e.g. crimping)in which there is a control means responsive to a sensed condition; (c)thread finishing utilizing diverse texturing operations; (d) threadfinishing via fluid jet having orthogonally arranged flow paths; (e)thread finishing via fluid jet having opposed reasonance chambers; (f)thread finishing via fluid jet having opposed fluid passageways.

With respect to processes for shaping or treating plastic articles, thepresent invention is related to the areas of: (g) processes involvingtwining, plying or braiding or textile fabric formation; (h) processesinvolving the formation of continuous or indefinite length work; (i)shaping filaments by extrusions.

With respect to textile spinning, twisting and twining, the presentinvention is related to the areas of (j) the strand structure ofmultifilament yarns wherein the filaments are crimped or bulked; (k) jetinterlacing or intermingling of filaments.

With respect to the field of textiles, fluid treating apparatus, thepresent invention is related to the area of gas, steam, or misttreatment with continuous textile feed and discharge.

2. Description of the Prior Art

Many prior art patents are related to the process of the presentinvention. The closest patent is believed to be U.S. Pat. No. 4,505,013.Other patents of interest include the following U.S. Pat. Nos.:4,355,592; 4,222,223; 3,010,270; 4,343,146; 3,953,962; 3,898,719;3,874,045; 3,874,044; 3,811,263; 3,251,181. None of these prior artpatents are believed to enable the process of the present invention. Thepresent invention enables the continuous, high speed production of ahighly and uniformly entangled multifilament carpet yarn. The prior artdoes not provide any means for achieving a degree and uniformity ofentanglement at the process speeds of the present invention.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed towards a continuous, integrated, highspeed process for making a multifilament carpet yarn having a very highdegree of filament intermixture. The process comprises the steps of:

(a) forwarding an undrawn multifilament carpet yarn;

(b) drawing the yarn until the elongation of the filaments has beenreduced to an acceptable level for end use in carpeting applications,the drawn yarn having a denier between 2000 and 4000, the drawnfilaments each having a denier between 18 and 35;

(c) crimping the drawn filaments with a jet crimping means;

(d) over-feeding the yarn to an intermixing jet, the degree ofover-feeding being between 1% and 10%;

(e) intermixing the drawn, textured yarn in the intermixing jet, theintermixing jet creating a degree of entanglement of the filamentswhereby a standard deviation of less than 6.0 results upon conducting aStandard Yarn Streak Potential Test; and

(f) taking up the textured, interlaced yarn at a speed of at least 800meters per minute.

The present invention is most particularly concerned with intermixingthe filaments to a very high degree. "Intermixing", as used herein is tobe contrasted with entangling, interlacing and texturing. Interlacing isused to slightly entangle filaments together, so that the interlacedmultifilament yarn will undergo subsequent processing with reducedflaring and individual filament wrapping. Texturing is a term used todescribe mechanical deformation of filaments in order to form a textured(i.e. "crimped") filament. Both texturing and interlacing can beperformed in conjunction with high speed yarn processing by using fluidjets. However, neither texturing nor interlacing creates a high degreeof filament entanglement. Entangling, on the other hand, is generallyutilized to create a degree of filament entanglement which is equivalentin degree to the amount of filament entanglement created by the"intermixing" process of the present invention. However, entanglementprocesses of the prior art have been notoriously slow, because it hasnever (heretofore) been possible to achieve an exceedingly high degreeof filament entanglement at yarn take-up speeds in excess of about 800meters per minute. Thus, the term "intermixing", as used herein, isdefined to include only processes which enable (1) a degree ofentanglement which yields a standard deviation of less than 6.0 whenmeasured by a Standard Yarn Streak Potential Test described below while(2) the take-up speed is greater than 800 meters per minute. It has beensurprisingly found that such a process is possible, and to-date the onlyknown way of carrying out such a process is to use both supersonic steamimpact on the traveling yarn along with a particular fluid jet designwhich will efficiently and continuously entangle the filaments to adegree which renders a standard deviation of less than 6.0 uponconducting a Standard Yarn Streak Potential Test. The process providesan additional advantage of enabling a high speed method for producing acarpet yarn which has very good tip definition in comparison with priorart carpet yarns which were made at take-up speeds below 800 meters perminute

It is an object of the present invention to provide a high speed,one-step process for intermixing the filaments of a bulked continuousfilament carpet yarn.

It is a further object of the present invention to enable the high speedproduction of a multicolored carpet yarn having a low streak potentialas measured by the Standard Yarn Streak Potential Test as definedherein.

It is a further object of the present invention to improve the degree offilament entanglement for processes having take-up speeds above 800meters per minute.

It is a further object of the present invention to enable, at speedsgreater than 800 meters per minute, the production of a bulkedcontinuous filament yarn having a woolish look and texture.

It is a further object of the present invention to eliminate the needfor commercial processes to have a plying step necessary in theproduction of low-streak bulked continuous filament carpet yarns.

It is a further object of the present invention to produce a bulkedcontinuous filament carpet yarn having filaments which are entangledalong their entire length rather than at nodal points.

It is a further object of the present invention to combine a pluralityof yarns having different coloration potentials, while creating aproduct which is made both at high speed and with a low streakpotential.

It is a further object of the present invention to utilize steam atsupersonic speeds in order to achieve intermixing of the filaments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of a process of the present invention.

FIG. 2 is a schematic of an alternative process of the presentinvention.

FIG. 3 is a schematic of yet another alternative process of the presentinvention.

FIG. 4A is a longitudinal cross-sectional view of a high speed jetentangling insert of the present invention.

FIG. 4B is an exploded perspective view of the jet intermixing insertand its housing and fluid supply

FIG. 4C is a perspective cut-away view of the insert installed in thehousing, together with a simulation of a yarn traveling through theintermixing insert.

FIG. 5 is another alternative process of the present invention

FIG. 6A illustrates an untrafficked, carpet made without the advantagesof the present invention, while FIG. 6B illustrates the carpet of FIG.6A after trafficking.

FIG. 7A illustrates an untrafficked carpet made with the advantages ofthe present invention, while FIG. 7B illustrates the carpet of FIG. 7Aafter trafficking.

FIG. 8 depicts a carpet yarn process in which two primary yarns areco-spun.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates, in schematic form, the process of the presentinvention. An undrawn feed yarn (1) is taken off of a package (2), fedthrough a first guide (3) and makes about 3 wraps around a first godet(4). The first godet (4) is used to pretension the yarn. The yarn isthen drawn between a second godet (5) and a third godet (6). The yarnmakes 7 or 8 wraps around both the second godet (5) and the third godet(6). The yarn (1), now drawn, is then texturized in a texturizing tube(7). This texturizing tube is described in U.S. Pat. Nos. 3,908,248 and3,714,686, which are hereby incorporated by reference. The nowtexturized yarn (1) then travels over a direction changing roll (8) anda tensioning device (9) after which the yarn contacts a fourth godet(10) and a fifth godet (12). The texturized yarn is over-fed from thefourth godet (10) to the fifth godet (12). Between these godets (10 and12) is an intermixing jet (11). After exiting the fifth godet the yarn(1) passes over another direction changing roller (13) and onto thetraverse roll (16) of a winder (14). A yarn package (18) is then builtup upon a package tube not shown, the package (18) being driven by afriction roll (15). A second package tube is to be rotated into contactwith the friction roll (15) after a full package (18) is built up upontube.

FIG. 3 illustrates a schematic of a preferred process of the presentinvention. In this process, eight (only four packages (2) are shown)primary, feed-yarns (1), held on packages (2), are each threaded throughindividual guides 3. All eight of these primary feed-yarns (1) are thenpassed through a second guide (19) and a preinterlacer (20), and arethen fed to the pretensioning godet (4). The primary yarns (1) are thendrawn between the second godet (5) and the third godet (6), and thedrawn yarns (1) are then texturized in the texturizing tube. Afterpassing over direction changing rolls 8 and 9, the yarn (1) pass aroundthe fourth godet (10). An additional yarn (25) herein termed an "accentyarn" is merged into the drawn, texturized yarns (1) on the fourth godet(10). The accent yarn is preferably also solution dyed (i.e. pigmented).The accent yarn (25) is supplied from a package (26), the accent yarnpassing through two guides (27 and 28) before going onto the fourthgodet (10). Upon exiting the fourth godet (10), the yarns (1 and 25) areintermixed in the entangling jet (11). The yarns are over-fed to theintermixing jet (11) by having the surface speed of the fourth godet(10) higher than the surface speed of the fifth godet (12). The yarns (1and 25) then pass over a direction changing guides (13) and onto winder14, and are wound to form package 18, as described above.

FIGS. 4A, 4B, and 4C show detailed view of the intermixing jet (11)which is utilized to intermix the filaments in the process of thepresent invention. The intermixing jet (11) is comprised of an inserthousing (29) having an insert (30) which is positioned therein. The flowof steam is partially confined by O-rings 31 and 32, these O-ringsforcing the steam to travel through a slit (33) in the insert (30),i.e., the O-rings 31 and 32 preventing the steam from escaping betweenthe housing (29) and the insert (30). The insert (30) is locked intoplace with a setscrew (34), and steam is supplied to the housing via anopening (not shown) to which is attached a threaded connector (35). Theslit (33) in the insert (30) is approximately 1.4 millimeters wide, andpreferably extends approximately 180 degrees around the circumference ofthe insert. As a result of the shape of the slit (33), the yarntraveling through the intermixing jet (11) cannot escape continuousimpingement of supersonic steam which is entering the yarn-impactchamber 36 via slit 33. The shape of the slit (33) creates aninescapable flow of steam. It is believed that this inescapable flow islargely responsible for the "continuous intermixing" (to bedistinguished from "nodal entanglement") produced by the presentinvention. Nodal entanglement creates spaced regions of high filamententanglement between which are regions virtually free of filamententanglement. The "continuous intermixing" form of entanglement producedby the process of the present invention contrasts with nodalentanglement in that the filaments are entangled along the entire lengthof the yarn, there being no regions without a fairly high degree offilament entanglement.

The process of the present invention is "continuous" in time. That is,the process carries out drawing, texturizing, and intermixing all atonce. In contrast, commercial prior art processes have utilized aseparate and expensive plying step in order to create a carpet yarnwhich had a low streak potential, as measured by the test describedbelow.

The process of the present invention is "intergrated" in that the stepsof drawing, texturizing, and intermixing are carried out in a singleoperation rather than as separate operations which require separate yarnwinding steps. Prior art commercial processes which utilizing plying tocreate a low streak-potential product also require an additional windingstep, which increases manual handling, energy consumption, and costs.

The process of the present invention is "high speed" in that the yarnmust be taken up at a speed of at least 800 meters per minute. Prior artprocesses which have produced a jet-entangled yarn having astreak-potential as low as that of the present invention have operatedat significantly lower speeds--i.e., below 800 meters per minute andgenerally between 100 and 500 meters per minute. This is because theprior art has not had the means to create a high degree of continuousfilament intermixing at a high speed.

"Crimping" has been defined above as mechanical deformation of filamentsin order to form a texturized filament Although the crimping may becarried out in a variety of manners, it is most preferable that theprocess utilize the crimping tubes taught in U.S. Pat. Nos. 3,908,248 or3,714,686.

The process illustrated in FIG. 1 can be carried out with an uncolored,dyeable feed yarn, with a dyed feed yarn, or with a precolored(pigmented) feed yarn. The high degree of intermixing (for a yarn ofonly a single color) provides the advantage of producing, at high speed,a yarn which will show delayed "ugly-out" when made into a cut pilecarpet. "Ugly-out" is a term used to describe the loss of tip definitioncaused by heavy traffic on the carpet. Heavy traffic causes thefilaments of each yarn to flair out, causing a "mushy" and "indistinct"look which is undesirable. It has been found that the intermixed yarn,when made by the process described herein, tolerated more traffic whileexhibiting less ugly-out than carpets made from carpet yarns which hadbeen entangled to a lesser degree.

The process of the present invention is advantageously carried out asshown in FIG. 2. The greatest assets of the present invention lie in itsadvantages for combining yarns which have significantly differentcoloration potentials. The high degree of entanglement of textured yarnsproduces a yarn which not only exhibits delayed ugly-out, but also hasfewer streaks than prior art carpet yarns produced at similar speedswithout a plying step. Streaking is always a problem with bulkcontinuous filament carpet yarn comprising filaments of substantiallydifferent coloration, and it has long been the practice to ply two yarnstogether in order to reduce the potential for streaking to result. Theplying operation is an additional step and is time consuming andexpensive. The process shown in FIG. 2 may utilize, for example, onewhite (undyed) polyamide primary feed yarn (1) which is acid dyeable,one black (pigmented) polyamide tonal primary feed yarn (21) and a fullydrawn, untextured, red (pigmented) accent yarn (25). The combined yarns,once wound onto the package (18), will appear as a grey yarn (tonal yarnmixed evenly with the white feed yarns) along with a red accent yarnwhich stays bundled together (i.e. is not intermixed). In a carpet madefrom this yarn, if the white yarn was left undyed the carpet wouldappear to have a grey base and a red "berber" effect. The grey iscreated by the high degree of mixing of black and white filaments andthe red "berber" effect is created by the lack of mixing of the redfilaments with either the black or white filaments. The entangling jet(11) has been found to effectively intermix only the crimped filaments.The untextured filaments of the accent yarn (25) are not intermixed bythe entangling device (11). Rather, these filaments remain relativelyintact as a bundle. It has been theorized that it is the excessivelength (i.e., potential slack) present in crimped yarns together withthe fullness (i.e., low density) present in crimped yarns which allowsthe impact of a fluid stream to create a greater degree of filamententanglement than with uncrimped yarns.

The present invention is most useful in the manufacture of bulkedcontinuous filament carpet yarns which, when drawn, have a denierbetween 2000 and 4000, the drawn filaments each having a denier between18 and 35.

The present invention pertains to a process which intermixes drawn,textured filaments in the intermixing jet, the intermixing jet creatinga degree of intermixing of the filaments whereby a standard deviation ofless than 6.0 results upon conducting a Standard Yarn Streak PotentialTest. The Standard Yarn Streak Potential Test is conducted as follows:

Two primary feed yarns are drawn, textured, intermixed, and wound onto apackage. One of the feed-yarns is a 9100 denier (before drawing), 135filament semi-dull bulked continuous filament white yarn. The other feedyarn is a 2625 denier (before drawing) 42 filament black bulkedcontinuous filament feed-yarn. The resulting drawn (by a factor of3.2×), textured, intermixed, wound product is used to make a 0.1 guage,level loop, 28 ounce/square yard carpet having a pile height of 3/16inches. The carpet is tested by making colorimetric measurements withthe Small Angle View attachment on a Macbeth 1500 colorimeter at between65 and 100 different locations on the carpet. The Macbeth 1500colorimeter analyzed an area of approximately 2 cm×1 cm, this area beingoriented in the direction of tufting (i.e., along the length of theyarn). The values obtained were averaged to establish a standardreference point. Then another 35 to 50 additional measurements were madeand compared against the standard reference point. The DL's wererecorded, from which a standard deviation was calculated. The standarddeviation is a quantitative measurement of the degree of color mixingobtained in the sample. It should be emphasized that the Standard YarnStreak Potential Test requires that: (1) the yarns used are: (a) a drawnand textured 2600 denier/135 filament semi-dull white yarn, and (b) a750 denier/42 filament black yarn; and (c) that the standard referencepoint and the 35 to 50 additional measurements are made on the same typeof carpet as described above and that the measurements are taken in thesame manner as described above.

The Standard Yarn Streak Potential Test can be carried out in order todetermine whether any process which draws, texturizes, and intermixesvia fluid jet will create a product having a standard deviation of lessthan 6.0. One must simply substitute the feed-yarns (described above)into the process, make the carpet according to the description above,and analyze the carpet as described above. It is most preferred that thedegree of intermixing is high enough so that the resulting standarddeviation is less than 5.0.

It has been determined that the intermixing jet utilized in the presentinvention should have a yarn-impact chamber (36, as shown in FIG. 4A)diameter between 3/64 inches in diameter and 3/16 inches in diameter Ithas also been found that the length to diameter ratio within theyarn-impact chamber (36) is most preferably 2.4. It has been found thatan L/D of 2.0 does not result in sufficient intermixing and that an L/Dof 2.8 results in a product having too much "stiffness" (i.e., a harshhand). The slot (33) is most preferably about 0.044 inches wide and mostpreferably extends 180 degrees around the yarn-impact chamber, creatingan "inescapable" jet of fluid to impact the yarn in the yarn-impactchamber. It has been found that the supersonic flow of steam causes thecreation of filament loops when the steam impacts the yarn travelingthrough the intermixing device. These loops create a "wool like"appearance in the resulting product.

The process of the present invention may additionally comprise the stepof extruding the primary yarns immediately prior to forwarding theprimary yarns to the second godet (5). This creates the advantageouseconomic effect of elimination of the winding step used to make thepackages (2, 22 and 26) shown in FIG. 2. In addition, although theaccent yarn is generally thought to provide a desired coloration effect,one could utilize an antistatic yarn in order to impact an antistaticcharacteristic to the resulting product. The antistatic yarn (or theaccent yarn, for that matter) could be a multifilament or amonofilament, and could be predrawn and pretextured or merely predrawnand untextured.

EXAMPLE 1

The process was carried out as shown in FIG. 2. A 6700 denier, 58filament, undrawn nylon-6 white feed yarn (1) was fed from a package (2)through two guides (3 and 19), following which the feed yarn (1) cameinto contact with a pretensioning godet (4). As used herein, the term"godet" is meant to include both the large driven roll along with thesmaller "idler" roll. When the yarn is described as being "wrappedaround the godet", it is, of course, meant that the yarn is wrappedaround the driven roll and the idler roll as a pair, rather than beingwrapped more than 1 full circumference around any single roll.

A 726 denier 14 filament, undrawn (approximately 460% elongation tobreak), nylon-6, black "tonal" yarn (21) was taken from a second package(22), this yarn also passing through two guides (23 and 24) beforemerging into the white yarn (1) on the pretensioning godet (4). Aftermaking three wraps on the pretensioning godet, the combined feed andtonal yarns (1 and 21) made seven wraps around a second godet (5). Thesecond godet (5) was maintained at a temperature of approximately 50° C.The surface speed of the second godet (5) was 372 meters per minute. Theyarns (1 and 21) then made seven wraps around a third godet (6) having asurface speed of 1200 meters per minute and a temperature of 160° C. Ofcourse, the yarns (1 and 21) were drawn approximately 3.2× between thegodet (5) and the third godet (6). Upon contacting the third godet (6),an antistatic yarn (40), supplied from a yarn package (41) was mergedinto contact with the now drawn yarns (1 and 21). The antistatic yarn(40), the feed yarn (1), and the tonal yarn (21) were then texturized ina texturizing tube (42) similar to those described in U.S. Pat. Nos.3,908,248 and 3,714,686. The texturizing tube was supplied with hot air(450° C.) at a pressure of 85 psi (source of hot air not shown). Aftertexturing, the combined feed yarn (1), tonal yarn (21), and antistaticyarn (40) were passed partially around a direction changing roll (8) andthen around a tensioning device (9), and finally around a fourth godet(10). The surface speed of the fourth godet was 905 meters per minute. A220 denier, 14 filament, nylon-6, red "accent" yarn (25), supplied froma package (26), was then merged into contact with the already combinedand texturized yarns 1, 21 and 40. After making 5 wraps around thefourth godet (10), the now combined yarns (1, 21, 40 and 25) were passedthrough an intermixing jet (11). The intermixing jet had a 180 degreeslit which was 0.044 inches wide, this slit being supplied withsaturated steam (177° C.) at 120 psig. The intermixing jet had ayarn-impact chamber which had a length of 0.3 inches and a diameter of0.125 inches, and the intermixing jet was proportioned as shown in FIG.3A. The impact of the steam on the traveling yarns created a high degreeof filament entanglement between the feed yarn (1) and the tonal yarn(21) and also created filament loops which protruded from the highlyentangled filaments at random intervals. The accent yarn was tied intothe remaining filaments, but was not intimately mixed thereinto. The nowintermixed yarns (43) then made 5 wraps around a fifth godet (12). Thesurface speed of the fifth godet (12) was 860 meters per minute Theintermixed yarns (43) then passed around a direction changing roll (13)and were then wound to form a package (18) on a Rieter winder, ModelJT/A, (14), at a speed of 864 meters per minute. The fourth and fifthgodet pairs (10 and 12) were not heated, i.e. they were kept at roomtemperature. The yarn tension at specific points (A-G, as shown inFIG. 1) in the process was as follows:

    ______________________________________                                        Designated     Tension                                                        Point in Process                                                                             (Total, in Grams)                                              ______________________________________                                        (a)            6000                                                           (b)            80                                                             (c)            10                                                             (d)            40                                                             (e)            10                                                             (f)            100                                                            (g)            140                                                            ______________________________________                                    

The resulting product was a yarn having textured, very evenly mixedwhite and black filaments together with a bundle of untextured, unmixedred filaments. When made into a carpet, the yarn appeared, from adistance, to be heather grey with flecks (i.e. points) of red randomlydispersed to give a berber effect. The white feed-yarn (1) could then bedyed in any of a wide variety of colors, as desired.

EXAMPLE 2

The process was carried out as shown in FIG. 1. An 1800 denier, 99filament, undrawn, nylon-6 white feed-yarn (1) was fed from a package(2) through a guide (3) and onto a pretensioning godet (4), where theyarn was wrapped around the godet three times. The undrawn yarn had aelongation to break of approximately 460%. The yarn (1) was then wrappedseven times around a second godet (5), this second godet (5) beingmaintained at a temperature of 50° C. The second godet pair had asurface speed of 372 meters per minute. The yarn was then drawn betweenthe second godet (5) and a third godet (6), which the yarn was wrappedaround a total of seven times. The third godet (6) had a surface speedof 1200 meters per minute and was maintained at a temperature of 160° C.Upon exiting the third godet (6), the now drawn yarn (1) entered atexturing tube as described in Example 1. The texturizing tube wassupplied with hot air (450° C.) at a pressure of 85 psi. Aftertexturizing, the now drawn and texturized feed yarn (1) was passedpartially around a direction changing roll (8) and then around atensioning device (9), and finally around a fourth godet (10). Thefourth godet (10) was not heated (i.e. was at room temperature) and wasmaintained at a surface speed of 880 meters per minute. After making 5wraps around the fourth godet (10), the yarn (1) next passed through anintermixing jet (11). The intermixing jet had a 180 degree slit whichwas 0.044 inches wide, this slit being supplied with saturated steam(177° C.) at 120 psig. The intermixing jet (11) had a yarn-impactchamber which had a length of 0.3 inches and a diameter of 0.125 inches,and the intermixing jet was proportioned as shown in FIG. 3A. The impactof the steam on the traveling multifilament yarn created a high degreeof filament entanglement and also created filament loops which protrudedfrom the highly entangled filaments at random intervals. The yarn (1)then made 5 wraps around a fifth godet (12). The surface speed of thefifth godet (12) was 860 meters per minute. The yarn (1) then passedaround a direction changing roll (13) and was then wound to form apackage (18) on a Rieter Winder, Model JT/A, (14), at a speed of 875meters per minute. The fourth and fifth godet pairs (10 and 12) were notheated, but instead were kept at room temperature. The yarn tension atspecific points (A-G, as shown in FIG. 3) in the process was as follows:

    ______________________________________                                        Designated Point                                                                             Tension                                                        in Process     (Total, in Grams)                                              ______________________________________                                        (a)            3000                                                           (b)            80                                                             (c)            10                                                             (d)            40                                                             (e)            10                                                             (f)            100                                                            (g)            140                                                            ______________________________________                                    

EXAMPLE 3

The process was carried out according to the schematic illustrated inFIG. 3. Eight 1089 denier, 14 filament undrawn precolored nylon-6 feedyarns (1) were feed from eight packages (2). Only four of the eightpackages are shown in FIG. 3. Four of the eight yarns were brown, twoyarns were beige, one yarn was orange, and one yarn was white. Each ofthe yarns (1) was first threaded through an individual guide (3),following which all eight yarns (1) were together threaded through agroup guide (19). The feed yarns (1) were then directed through apreinterlacer (20). The preinterlacer (20) was supplied with compressedair at approximately room temperature and at a pressure of 150 psig. Thepreinterlacer (20) had a circular yarn throughout passageway 0.1875inches in diameter and 0.30 inches long. The preinterlacer had three jetorifices, each of which intersected the axis of the yarn throughputorifice at an angle of 90 degrees. The axes of the three jet orificeswere in a single plane and were positioned equidistantly from oneanother so that there was no net directional effect on the yarns beingpreinterlaced. Each jet orifice had a diameter of 0.0625 inches. Afterpassing through the preinterlacer (20), the feed yarns (1) came intocontact with a first (pretensioning) godet (4). After making three wrapsaround the first godet (4), the combined feed yarns (1) made seven wrapsaround a second godet (5). The second godet had a surface speed of 372meters per minute and was heated to a temperature of 50° C. From here,the yarns (1) made ten wraps around a third godet (6), the third godet(6) having a surface speed of 1200 meters per minute and a temperatureof 160° C. The yarns (1) were drawn 3.23× between the second godet (5)and the third godet (6). The yarns (1) were texturized in a texturingtube (7) similar to those described in U.S. Pat. No. 3,908,248 and3,714,686. The texturizing tube was supplied with hot air (450° C.) at apressure of 85 psi. After texturizing, the feed yarns (1) were passedpartially around a direction changing roll (8) and then around atensioning device (9), and finally made 5 wraps around a fourth godet(10). An antistatic yarn (25), supplied from a package (26), was mergedwith the feed yarns (1) on the fourth godet (10). The fourth godet wasunheated, and had a surface speed of 905 meters per minute. The combinedyarns (1, and 25) then passed through an intermixing device (11) andthen made 5 wraps around a fifth godet (12) which had a surface speed of860 meters per minute and was also unheated. From here the combinedyarns (1, and 25) passed over a direction changing roll (13) and finallywere taken up on a Rieter Winder, Model JT/A, (14), at a speed of 868meters per minute. A yarn package (18) was formed by the winder (14).The yarn tension at specific points (A-G, as shown in FIG. 3) in theprocess was as follows:

    ______________________________________                                        Designated Point                                                                             Tension                                                        in Process     (Total, in Grams)                                              ______________________________________                                        A              5000                                                           B              80                                                             C              10                                                             D              40                                                             E              10                                                             F              100                                                            G              140                                                            ______________________________________                                    

In the process described above, the intermixing jet was substantially asshown in FIGS. 3A, 3B, and 3C. The jet (11) had an 180 degree slit whichwas 0.044 inches wide, this slit being supplied with saturated steam (at177° C.) at 120 psig. The jet (11) had a yarn-impact chamber which had alength of 0.3 inches and a diameter of 0.125 inches, and the intermixingjet was proportioned as shown in FIG. 3A. The product exhibited a veryhigh degree of entanglement of the filaments, and filament loops alsoprotruded from the resulting product

EXAMPLE 4

This example is intended to show how the Standard Yarn Streak PotentialTest may be applied to a process in order to determine the standarddeviation which the process is capable of producing. A process (carriedout as shown in FIG. 5) was subjected to the Standard Yarn StreakPotential Test in order to determine whether the resulting standarddeviation was less than 6.0.

Two primary feed yarns (1 and 21) were drawn, textured, intermixed, andwound onto a package. The first feed yarn (1) was a 9100 denier (beforedrawing), 135 filament semidull (0.3 percent TiO₂), continuous filament,white polycaprolactam yarn. The second feed yarn (21) was a 2625 denier(before drawing), 42 filament, black continuous filament polycaprolactamfeed yarn. These yarns were drawn, textured, intermixed, and taken upunder the conditions described in Example 2. Thus, Example 4 is, ineffect, a description for subjecting the process of Example 2 to theStandard Yarn Streak Potential Test. The resulting product was used tomake a 0.1 gauge, level loop, 28 ounce per square yard carpet having apile height of 3/16 inches. The carpet was tested by making colorimetricmeasurements with the Small Angle View attachment on a Macbeth 1500colorimeter. Measurements take by the colorimeter represented thepercent of light reflected upon subjecting a portion of the carpet to agiven amount of light. Measurements were taken at 50 different locationson the carpet. The Macbeth 1500 colorimeter measured an area ofapproximately 2 centimeters by 1 centimeter, this area being oriented inthe direction of tufting (i.e. along the length of the yarn). The valuesobtained were averaged in order to establish a standard reference point.After calculation of the standard reference point, another 75measurements were made, each being compared with the standard referencepoint. The DL's were recorded (the DL's were based on the CIELAB colororder system), and a standard deviation of 5.34 was calculated.

EXAMPLE 5

This example is intended to show how the Standard Yarn Streak PotentialTest may be applied to a process similar to that discussed in Example 4.The process was carried out as shown in FIG. 5 and as described above inthe process description related to FIG. 5. However, in place of theintermixing device (11), a conventional interlacer was utilized. Theinterlacer used was exactly the same as the preinterlacer (20) utilizedin FIG. 3. However, in this Example, the interlacer (2)) of FIG. 3 wasused in place of the intermixing device (11) of FIG. 5. The interlacer(20) was made and operated at the same specifications described inExample 3. Again, two primary feed yarns were drawn and textured exactlyas in Example 4. The feed yarns were identical to those used in Example4. The interlacer was supplied with compressed air at 150 psig. Theresulting product was used to make a carpet of the same specificationsas described in Example 4. Colorimetric measurements were taken exactlyas described in Example 4. A standard deviation of 9.27 resulted.

A comparison of Examples 4 and 5 illustrates the need for the use of adevice which is capable of intermixing the filaments rather thaninterlacing the filaments. A visual examination of the carpet producedin Example 4 revealed that the carpet produced via Example 4 exhibited a"solid heather" appearance. In contrast, a visual examination of thecarpet produced via Example 5 revealed that the carpet produced viaExample 5 exhibited a "random stria" appearance. It has been conceivedthat any carpet exhibiting a standard deviation of less than 6.0 (asmeasured by the test) will also exhibit a "solid heather" appearance,while any carpet exhibiting a standard deviation of greater than 9.0(again, as measured by the test) will also exhibit a "random stria"appearance. The low streaking present in the solid heather carpets isconsidered to be highly desirable, and has been achieved in the pastusing both relatively low speed processes and plying processes.

FIGS. 6A and 6B illustrate the effect of traffic on a carpet made usingprior art technology. The carpet is new in FIG. 6A, while FIG. 6Billustrates the same carpet after 133,000 "traffics". FIG. 7A and 7Billustrate a carpet which is identical to the carpet of FIGS. 6A and 6B,except that the carpet shown in FIGS. 7A and 7B utilized an intermixingstep in the yarn production process. FIG. 7A represents this carpet whennew and FIG. 7B represents this carpet after 133,000 "traffics". Acomparison of FIG. 6B with FIG. 7B illustrates the dramatic differencein tip definition after heavy trafficking. Obviously, the carpet madewith the intermixed yarn (FIG. 7B) was far more durable in terms of tipdefinition (i.e. "ugly-out") than the carpet illustrated in FIG. 6B,which was made using a prior art interlaced yarn which had 10-12 nodesper meter.

FIG. 8 depicts a process in the manner of FIG. 5, except the carpetyarns are co-spun in a single process. Primary feed yarn 101 is spunfrom a conventional spinning device 102. A second feed yarn 103 ofdifferent characteristics is spun from spinning device 104. The twoyarns are converged through eyelet guides 3 and 19 prior to beingcontacted by pretensioning godet 4. The combined yarns are then drawnbetween godets 5 and 6, textured in device 42, intermixed in jet 11 andwound into a package 15.

The carpets shown in FIGS. 6A and 6B are velvet plush (cut loop) carpetshaving a pile height of 3/8 inches, and 48 oz./square yard of face yarn.The yarns used in both carpets consisted of: (a) an 1800 denier nylon-6bulked continuous filament space dyed yarn, which was plied with (b) twoends of 2000 denier, stock dyed, nylon-6 spun yarn. The spun yarns wereeach made from 8 inch burgundy colored staple. Each of the spun yarnshad 31/2 twists per inch, and the plying process inserted 11/2 twistsper inch into the final yarn. The space dyed yarn was dyed black andbrown. In the carpet shown in FIG. 5A, the 1800 denier space dyed yarnwas interlaced so that it contained 10-12 nodes per meter, while in thecarpet shown in FIG. 7A, the 1800 denier space dyed yarn was intermixedso that it had virtually continuous filament entanglement.

FIGS. 5A, 5B, 7A and 7B illustrate the fact that the process of thepresent invention is capable of making a yarn at high speed which hasimproved tip definition over prior art carpets which are made at highspeed with entanglement via interlacing. Improved tip definition is animprovement for any carpet, i.e. both solid an multicolored carpets. Thereason for using multicolored yarns in FIGS. 5A and 7A was simply forpurposes of making the improved tip definition more conspicuous.

We claim:
 1. A continuous high speed process for the manufacture of a"berber" effect carpet yarn comprising the steps of:overfeeding at leastone primary bundle of drawn, crimped carpet filaments of 18 to 35 denierper filament with an accent bundle of drawn, uncrimped carpet filaments,the total denier of the primary bundle and accent bundle being2,000-4,000, through the mixing chamber of an intermixing jet, thechamber having a length to diameter ratio of about 2.4 and furtherhaving a slit of about 180° around the chamber for admitting steam undersupersonic flow conditions; providing said steam to said chamber tocontinually intermix the crimped filaments along the entire lengththereof, the accent yarn remaining substantially intact and thereafterwinding the yarn at a speed of at least 800 meters per minute.
 2. Thecontinuous process of claim 1 wherein at least one primary bundle ofdrawn, crimped carpet filaments contains a texturized antistatic yarn.